5.4 Rocks from reefs

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Vocabulary

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coral reef-a calcite structure built by coral animals in warm waters
atoll-a ring-shaped coral island

Outline

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Rocks from reefs

• Living coral
  • Coral animals are tiny relitives of jellyfish
    • They produce skeletons that form coral reefs
• How a reef forms
  • Coral animals absorbs calcium and changes it into calcite.
    • When the animals die, they leave calcite behind
    • They pile up forming reefs
• Limestone deposits from coral reefs
  • Coral reefs may rise above sea levels
  • This forms limestone
    • Limestone is found in mainly the USA